The subject matter disclosed herein relates generally to platelet therapy used in various medical applications, such as treatments for surgery or trauma. Specifically, the embodiments described relate to platelet activation and growth factor release in platelet rich plasma.
Platelet therapy is a wound healing treatment used for many types of injuries and conditions, such as nerve injuries, tendinitis, osteoarthritis, cardiac muscle injury, and bone repair and regeneration. Platelet therapy may also be used to speed up wound healing after surgery.
Generally, a doctor may draw blood from a patient; the blood is then centrifuged to generate platelet rich plasma (PRP). For in vivo platelet activation, the doctor may apply the PRP to the site without adding a platelet activator. Platelet activation, which includes growth factor release and clotting, is usually induced by the collagen within connective tissue. For ex vivo platelet activation, the doctor may trigger platelet activation within the PRP by adding a typical activator, such as thrombin, and then apply the activated PRP to the site.
For such ex vivo applications, bovine thrombin may be used to induce platelet activation. However, using animal-based thrombin may cause allergic reactions or possible contamination of the PRP with infectious agents. Alternatives to animal-based thrombin tend to be expensive and may still cause allergic reactions.
Further, there are some wound healing applications in which growth factor release is desired but the subsequent clotting is not. For example, a doctor may wish to inject a PRP sample with released growth factors into the site, which is a common treatment for joint injuries. Exposing a PRP sample to various types of light (e.g., infrared) may trigger growth factor release without the subsequent clotting. However, the experimental set-up is complex, which may be expensive and time-consuming to install in a laboratory. Additionally, the light exposure time for a sample may be long, which would subsequently increase the total time of the treatment.